Which one of the following is not a limiting factor for photosynthesis

Options

A. Chlorophyll
B. Light
C. Carbon dioxide
D. Oxygen

Answer

To determine which of the following is not a limiting factor for photosynthesis, we need to analyze each option provided in the question.

### Step-by-Step Solution:

1. **Understanding Limiting Factors**:
- A limiting factor is any condition or substance that can restrict the rate of a process. In the context of photosynthesis, it refers to any element that can limit the rate at which photosynthesis occurs.

2. **Analyzing the Options**:
- **Option 1: Chlorophyll**:
- Chlorophyll is the green pigment in plants essential for photosynthesis. It captures light energy, which is necessary for the process to occur. Therefore, chlorophyll is a limiting factor.

- **Option 2: Light**:
- Light is crucial for photosynthesis. The intensity of light directly affects the rate of photosynthesis; insufficient light can limit the process. Thus, light is also a limiting factor.

- **Option 3: Carbon Dioxide**:
- Carbon dioxide is a raw material used in photosynthesis. Plants absorb carbon dioxide from the atmosphere to produce glucose and oxygen. If carbon dioxide levels are low, photosynthesis cannot occur at its maximum rate. Hence, carbon dioxide is a limiting factor.

- **Option 4: Oxygen**:
- Oxygen is a by-product of photosynthesis. It is released after the process occurs and is not required for photosynthesis to take place. Therefore, oxygen does not limit the rate of photosynthesis.

3. **Conclusion**:
- Among the options provided, oxygen is the only one that is not a limiting factor for photosynthesis. Thus, the correct answer is **Option 4: Oxygen**.

### Final Answer:
Oxygen is not a limiting factor for photosynthesis.

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